The long-range goal of this project is to elucidate the biochemical basis of lead toxicity in the developing central nervous system. The initial objectives are to determine whether chronic lead exposure: 1) Is accompanied by alterations in the developmental patterns of the neuronal enzyme, Acetylcholinesterase; and the glial enzyme Butyrylcholinesterase. 2) Inhibits brain adenyl cyclase, an enzyme closely associated with synaptic transmission.